Fuel-injection mechanism



Nov. 27, 1928.

- 1,693,546 c. P. CLARK ET A| FUEL INJECTION-MECHANISM 4 Sheets-Sheet '1 Filed April 25; 1927 Nov, 27, 1928. 1,693,546

c. P. CLARK El AL FUEL INJECTION MECHANISM Filed April 25, 1927 4 Sheets-Sheet 2.

4 Sheets-Sheet 5 NOV. 27, 1 928.

C. P. CLARK ET AL FUEL INJECTION MECHANISM Filed April 25.- 1927 wees 1.693.546 C. P.-CLARK ET AL FUEL INJECTION MECHANISM Filed April 25. 1927 4 Sheets-Sheet 4 Nov. 27,1928;

IIII H W a hm wNH Patented Nov. '27, 1928.

- UNITED STATES,

PATENT "OFFICE.

CHARLES PAUL CLARK, OE OLEAN, CARL A.- B1TORNNSO1\T, OF WELLSVELE, YORK, ASSIGNORS T CLARK BROTHERS COMPANY, OF CLEAN, NEW YORK, A COR- JPORA'IION on NEW YORK.

I ruEL-Iumorrotr mncrmmsm Application filed April 25, 1927. Serial N0.186,329.

. This invention relates to an improvement in fuel injection mechanism, especially de-. signed for an internal combustion engine.

One of the objects of the invention is to provide for the regulation of the fuel injection into the-cylinder of an internal combustion engine controllable. from the working load whlch is laced on the engine so that for a light load t e supply of fuel is automatically decreased but for a heavy load an in-. crease in fuel is automatically provided. This is accomplished by' a suitable governor connected with a fuel, injection valve and.

regulated directly from the engine lay shaft.

A further object of the invention is to operate and. control fuelinjection mechanism I'directly from the engine lay shaft, .which regulates the'admission of fuel to the engine cylinders at properly timed intervals. A still further object of the invention 1s to arrange the fuel inlet in alignment with and in the direction of the exhaust ports of the cylinder, so as to insure of a thorough mixing of the fuel with the air used in scavenging the .cylinder. Compressed air only'isiused in the scavenging operation, and'near the completion thereof the fuel injection valve is opened directly in the cylinder to admit the fuel into the path of the air so as'to have a thorough mixing thereof prior to the explosion.

'In the usual type pf two cycle gas engine, the charge (air and gas mixture) isprecompressed to a few polimds above atmospheric pressure in a separate compression chamber. "The expanded gases exhaust thro'ugh cylinder ports uncovered by the piston near the end of the expansion stroke. .When their pressure has fallen nearly to atmospheric pressure, the precompressed charge enters-through ports also uncovered by the piston and sweeps out the.burned charge. The process of exhausting the burned gases, scavenging of the cylinderror admitting the fresh charge takes place through a period representing about one-fifth of the lengthof the expansion stroke and through an equal length at the first part of the compression stroke. During this process of scavenging, a large percentage of the fresh charge is lost through the exhaustp orts which are full open at the height of the scavenging period and remain open after this period is over, allowing a large percentage of the elevation of the same; I

Fig. 4 1s a vertical section through the fuel fresh charge to escape into the exhaust-line from the engine;

The space occupied by the gaseous fuel in i by insuring more complete scavenging, greater economy, and higher engine output.

In the acompanymg drawings F g-'1 1s a plan view of the complete fuel injection mechanism, as applied to an internal combustion engine Fig. 2 1s a top plan view of the main port1on of the lnjectlon mechanism;

- Fig. 3 is a vertical sectidn partly in" side i injection valve;

Fig. 5 is a cross section on the-line 55 of Fig.3;and

Fig. 6 is an end view.partly in section of the mechanism as applied to a twin engine.-

As illustrated in Fig. 1, the fuel isfdrawn from any suitable source of supply, throu ha pipe 1 to the pumpand compressor 2, w ich is operated by means of a-suitable motor 3,

and the fuel is forced from the compressor 2 througha pipe 4 to-a supply tank 5.

A reducing valve 6 is interposed in the pipe 7 which extends from 'thezsu pl tank 5' to the cylinder 8 for supplying tiie fiielthereto. This reducing valve-6 may be set tmdeliver the gaseous fuel at any suitable pressure desired, which will insure the most economical operation of the engine.

The internal combustion engine to which I this fuel injection mechanism may be applied may be of any suitable form and construction and is designated generally by the numeral 9. The main drive shaft 10 of the engine 9 has the fly-wheelsll fixed thereon, which are driven'from the piston 12 operated in the cyl- 'inder 8. The manner of this drive is conventional and, being ,well understood, is not set .forth in detail. v

A lay shaft 13 isiconnected in any suitable manner with the drive shaft 10 to be rotated therefrom. The outer end of the lay shaft 13 is mounted in'a bearing 14: supported by a suitable bracket 15 carriedby the engine housing. This bracket'is provided with a cover 16. The lay shaft 13 has .a cam 17 fixed there on, as clearly shown in Fig. 5, in position to engage a roller 18 carried by a lever 19 pivoted as at 20 to a bracket or arm carried by the supporting bracket 15. The outer end of the lever 19 supports a push rod 21, the upper end of which engages 'a horizontal lever 22 carried by a shaft 23 mounted in bearings 24 in the cover 16 w 1 The shaft 23' also carries a vertical arm 25 which is connected with a secondary push rod 26, as shown iii Fig. -3. .The outer end of the push rod 26 is operatively connected with one end of the valve lever 27 pivoted as at 28 in a bracket 29 carried by a-valve casing 30.

As shown in Fig.4, the opposite end of the lever 27 is connected with a valve stem 31 which carries a valve 32 in position toenga'ge a valve seat 33,3);the casing- 30. The valve stem 31 has jf disk -34 fixed thereon, and a spring 35 is interposed? between this disk 34 and the casihg-QiffThe interior of the casingcommunicates with the supply pipe ,7 and.

receives a charge of fuel therefrom.

As shown in Fig. 3, a sparkplug 36'is placed injthe. center of "the end cover of the cylinder 8,. and said sparkplugis'suitably governor, designated generally by the numeral 41, is used. This overnor may be ofconnected with a magneto 37. The valvecas-' ing 30 is secured to the-end of the cylinder 8 on one side of the spark plug 36. The gas-- eous fuel is dischar ed from the casing 30 about the valve 32 w en unseated in a direc tionat an angle to the center axis of the cylins der 8, and in the generaldirection of the exhaust vports 38 arranged in one side. of the cylinder in position to be covered and uncovered by the piston 12.

Arranged on the opposite side of the'cylinw der from the exhaust ports 38is an air port 39, through which compressed air is supplied to the cylinder for the scavenging operation. This port is likewise adapted to be covered by the piston, and on the side next to the port 39 the piston 12 is provided with the shoulder 40 in position to direct the compressed air in an upward direction toward the fuel injection valve 32. Itv will be noted that the fuel injunction valve is on the same side of the cylinder with the compressed air inlet ort, although the fuel valve is in the end 0 the cylinder but atone side of said end, and the exhaust ports are arranged on the opposite side of the cylinder. 7

For automatically controlling the supply of fuel through the pipe 7 to the cylinder, 21.

any suitable construction ut operates to control a valve stem 42- connected with suitable valve mechanism for automatically regulating the passage of fuel through the pipe The governor is operated by beveled ears 43, one of which is mounted on a sha 44.

The. opposite end of the shaft 44 carries a pinion 45 meshing with a gear 46 fixed on the outer end of, the lay shaft 13.- The gov-. ernor housing 47 is supported by a plate 48 carried by the supporting bracket; 15.

Inthe operation of the machine, tlegas or fuel is' pumped into the tank 5 by the compressor 2 from where it passes through the reducing .valve 6 and thepipe 7 into the cylinder 8. The lay shaft 13 being rotated by the main drive shaft 10 of the internal combustion engine causes a rotation of the governor 41 through the gearing 43, 45 and 46, and the shaft 44, and as the speed of'the drive shaft load, the speed is highest which, as stated forces the valve stem 42 downward to decrease the gas su'pply through the pipe 7. When the engine is operating at maximum load, the speedis less" and 'thevalve stem 42 is therefore elevated to admit. more fuel through the supply pipe 7. A

The rotation of the'lay shaft 13 from the drive shaft 10 causes a rotation of the cam 17, which rocks the lever 19 'on' its pivot 20, causing a periodical longitudinal movement 'of the push rod 21 and by reason of the bellcrank levers 22 and 25 mounted on the shaft- 23 causes a similar-longitudinal movement of the pushrod 26, which, in turn, rocks the le ver 27 and periodically moves the valve stem 31 inward against the tension of the spring 35 to unseat the valve 32 for admitting a 'supply of fuel into the cylinder 8. The position of the injector valve 32 is most advantageous and, as stated above, itis arranged at the opposite side of the cylinder from the exhaust ports 38 and in position to direct the dis charge of'fuel into the cylinder substantially in the direction of the exhaust ports. 7 Fresh air only is used in the scavenging operation to force out the exhaust gases from the cylinder through the exhaust ports 38; This fresh air is precompressed and admitted to the cylin der through the port 49 during the back stroke of the piston and a portion-of the return stroke, which uncovers this port, allowing the air to pass in and through the cylinder to force out the exhaust gases on the'return stroke of the piston. v

When the ports are partly closed, as shown in Fig. 3, the valve 32 is moved from its seat 33 to allow the injection of gaseous fuel into the cylinder. The shoulder 40 directs the 'iso admitted, resulting in an intimate mixture of gas and air. The motion of the mixture, when reaching the bottom of the cylinder, is deflected inward again, resulting in a revolv-- ing mass and insuring of complete mixture of the fuel and air. The fuel injection is completed when the working piston has traveled about forty-five'percent of the compression stroke, at which point the pressure in the cylinder and in the injection valve are about balanced.

In this manner, compressed air only is used for. the scavenging operation and the fuel is admitted directly into the cylinder for mixture with the air at the close of the scavenging operation, which insures of a thorough mixing of air and gaseous fuel. The relation ofthe injection valve, the compressed air port 39, shoulder 40 and exhaust ports 38 insures of this thorough mixing operation.

In the use of the invention as applied to a twin engine, as shown in Fig. 6, each ofthe cylinders 49 is provided with the injection valve mechanism operated by the levers 27 and push rods 26. A cross shaft 50 1s actu-- ated by gears '57 from the lay shaft 13, and this lay shaft 13 carries suitable cams for imparting'motion to the push rods 26. The operation is otherwise the same in connection with the twin engine, as set forth above for the two cycle engine.

lVe claim 1. In a device of the character described, the combination'with an internal combustion engine and cylinder therefor, of a lay shaft 2. In a device of the character described, the combination with an internal combustion engine, and means for admlttlng fuel thereto, of a cam actuated rocking lever connected with the engine, a push-rod operated by said rocking lover, a bell-crank connected with said push-rod and a second push-rod interbetween the bell-crank lever and the rocking lever, and a'second push-rod interposed be tween and for transmitting motion from the bell-crank lever to the fuel admitting means.

4. In a device of the character described, the combination witha valve, of a cam actuated rocking lever, a push rod operated by said rocking lever, a bell-crank connected with the push rod, and a second push rod interposed between and for transmitting mo ,tion from the bell-crank to the valve.

5. .In an internal combustion engine, the

combination with a cylinder, a valve for re};- ulating the admission of fuel thereto, a source of fuel supply communicating with the valve, a governor controlled valve interposed between the source of fuelsupply and the firstof the character described,v

posed between and for transmitting motion mentioned'valve, a lay shaft operated by the engine, and geared to and for actuating said governor controlled valve, cam actuated le'vers-controlled bysaid lay shaft, and a push rod connected with said cam actuated levers for actuating the-first-mentioned valve.

' CHARLES PAUL CLARK. CARL A. BJORNNSON;

tures.

In testimony whereofwe afiix our signa-r 

